Boiler.



G. ENGEL.

BOILBB.

APYLIUA'TION Hmm SEPT. s, 19'05.

Patented Feb. l, 191.

3 SHEETS-SHEET 2.

#CMM

Amann niiiTnn STATES PATENT onirica.

l GODFEEY ENGEL, OF PITTSBURG, PENNSYLVANIA.

BGIIJEB.

tHSTi specification of Leners raient. Patented Feb. 1, 1910. i Application filed September 8, 1905. Serial No. 277,554.

To all whom 'it may concern:

peratnre of said gases to a relatively great Be it knoivn that. l. (noni-*ner ENGEL, a

degree; Seventh, to obtain high furnace t cita/.en of the UnitedA States, residing in ellicieney; eighth. to permit the use of 'f Pittsburg, in the eountyet Allegheny and brit-lts or tiles nl simple and strong form 60 State ot' Pennsylvania, have invented i'- for the eonstruetion ot the various baille tain new and useful improvements in Boilwalls and partitions, to key together the of which the following is a speeilieation. seetionsof the. baille walls arranged longi- Iiii' invention relates to improvements in tudinzillv on the tubes, and to permit the boilers., and particularly to im' rovenients main dividing balile ivall to be vertical, and 65 l in water-tube boilers, all as. iereinaiter to be built of ordinary fire brie-lr laid with fully set forth and particularly pointed out close joints.. so to avoid Short-cireuiting in the Claims. of the gases, and to permit tlie battles to be The objects of my invention are, first. lo removed and replaced at will, and without produce a compact, etlieient. boiler of high i dillieulty; nintli, to malte the boiler Simple, 70

l capacit y in proportion to size, weight` and t compact and durable, to render stays unneclieating suraee; second, to avoid restriction essai-v and avoid the use of stayed members,

of eirculation and particularly restriction i to permit all parts to be made of rolled steel,

of sii-cams o mixed n'ater and steam, to i to obtain maximum strength with minimum cause the generating tubes Yto deliver i weight, to make. proper provision for ex- 75 ,1 t i, direetljyv into a relatirel)v large drum. at-

pansion and eontraetion, to maire all parts fouling ample Space for disengagement of t easy of access. to avoid the necessity ot' ex- \\'ater from the steam` and to canse :such disceptional .skill o.. the part of the attendants,

t engagement to take place pruicipall)` and l and to malte the ioiler easy to operate, as nearly as possible einirclv, in the upper clean and maintain; and lastly, to permit 80 i li-uni; third, to in ure thorough ainl rapid towing of the. boiler and to permit the use i natural circulation ol' the water in the i or" str/.invr drat't in the oieration thereof boiler, and the heating of the feed water to mean boiler teniperatnre before it en- (hie ot' 'the important objects of my prest-ounters the hottest portions of the boiler ent invention to improve the drums of 85 and t0 keep covered ivitli water all parte` I .sut-li boilers. and particularly the tube ofthe boiler which are exposedV to the direct .sheets thereof,A so that ivhile provision is action of the furnace gases: :uid fourth, to l inside for facilitating the insertion and prevent formation of scale. in the tubes and al withdrawal of the tubes, the tendency to drums and to canne all sediment to be det distortion and harmful `stretthinf:r of the 90 metal is reduced to a n'iinniiim and great,

with high economy of operation.

posited in mud cirunis; fifth, to insure d i tiveh7 small number of drains.. while insuri of invention illustrated in said drawings-110 steam, to avoid foaminit, to prevent proeeonomi in the metal is ell'ected, due to the i jeciion of spray.' into proxii'uity to the place i fact that. the distribution of the metal in l or places from which steam is taken oit; the formation oi'the tube seats is to a large sixth. to cause the. furnace gases to circulate t extent in the lines of strain. 95

l through the boiler in an improved manner, l, M v invention .is capable of being emt to equalize the circulation ofthe gases about bodied in boilers ot many ditferent types,

t and along; the surface of the tubes, to cause adapted for mani' rliti'erent uses and for use l said tubes to be exposed constantly to fresh l with man)Y dill'erent types of fuel. I have l portions of tlie furnace gases, avoiding dead l not attempted to illustrate all of the forms 100 spaces; or portions of tlie tube to which lie-it t in wliieh my improved invention may l is imparted intlirectl)- rallier than directly, l embodied, or to illustrate all of tlie modil to makevtlie entire heating surfaee of the firations and alternative constructions t boiler highly ellieient, and to provide a rell which "may De, emplovedor devised without i l atively long path for the gaie, in proporl departing from. the spirit. andv Scope of the 10b tion te the length of the tnbes and t ieir arinvention, but in the aceompanving drawf rangenu-nt, permitting the grouping of tlie ings have illustrated one type of boiler emi tubes in a relatively number ot' banks l bodvinz-zmy invention. sind boiler being of l of tubes, and permitting the :se of a relathe stationary type. Many of the features ing eliicient transfer of heat from 'the gases l are capable of being used in boilers of dit0 the water and the lowering of the tem l ferent eenstri'it-tion. and. in cornet-tion Wit-l1 other features ot' diii'erent construction and l the A-aid furnace. '.l`he drains, 2 and "3, and

inethod of operation than those. herein illustratetl, as will be apparent to those skilled in the art.

The particular' boiler illustrated herein as einbodving the features of invention hereinafter claimed, is of a novel type, comprising an upper steam and water drum and a plurality of lower drums (two. in the instaure shown). said lrunis all connected by tubes. the arrangement illustrated in the drawings resembling thc letter A. or a triangular figure. in ronnettioltwith 'the drums and tubes thus arranged I provide a furnace or other means for supplying heating and preferably. though not necesarily. i

muse said heating gases to tlow up along:l one ot' the inain .series or banks ot generati ing tubes connecting thc upper drum with thel lower drinn. and down along another such bank ot' tubes: and I ma)v also provide ineans whereby the heating gases are raus-eti tu tiow acros.,. aloner and around sub- -stantially the entire length and surface o each oi" such tubes, thereby providing a relativelyVA long path i'or the gasesrin a relativel)r compactV and simple boiler. keeping the. furnace-gases at all time4 in contat-t with or in effective proxiinit)Y tothe heating surface of the boiler, and cinistantlr exposing new portions of the gas-es to such heating surface. avoiding stafnation of the, gases and indirect trausini "in of heat.

in the art-onuxanyxn drawings, Figure i shows an elevation ot one forni ot' my im proved boiler. t'ie walls thereof being shown in section. Fig. 2 shows a detail side view of one, of the lor-:cr drums and its tubes, and illustrates the ronping of the latter. Fig. 3 shows a horizontal section of the boiler, looking downward. Fig. -t shows a detail end elevation .it the upper aud one of the lower drunir', and the tnbes'tbereof. Fig. 3 shows: a -loni-"itudinal section of one of thetramsversc bullies. Figs. t3 and i' are detai views of the longitudinal battles', Fig. ti being a perspective elevation of one of the baille sections` detached. and Fig. T showing;A in perspective'a row or wall of such s et tions. arranged as in practice. in connection with oiul of the tubes. Fig. h' shows a rertieal transverse section of the upper drinn, illustrating particularly the construction thereof, the sta-tion being taken on two liferent panes.

AFig. tl shows a side View of such drinn and its tubes. Fig, lll shows a plan view of a lower drinn and a eroswseetion of the tubes' thereof. and illu tiates the use of tubes as longitudinal bullies.

Referring to the drawings, l designates the said steam and water drinn', 2 and Il designate the said mnd tlrlnus: -l and di 'ignatc the said banks oi' inclined geperating tub-cs; V designates tubes connecting the mud drains 2 and Il; and T designates the tubes 4, 5 and t3 together constitute a closed circulating circuit. all within the inain heating chamber tortuetl by the brick walls S of the boilt setting. through which Pix-enit the water v ill eircnlate \er v rapidly and freely while the boiier is in operation. ln the particular construction shown the furnace. T. is et' the external type, being located in the :nain outside of the setting 8. This arrangement of the furnace has the advantage that combustion within the furnace is not prevented by the presence of relatively cool heating surfaces, there being no contact of the gases with the heating surface of the boiler until .said ga, pass' the bridge wall 9. However, I do not confine myself to this lot-ation ot' the furnace, but may locate il otherwise as may prove convenient, eiectire. or otherwise desirable.

Between the two banks of tubes, 4 and 5, I provide a main dividing wall or vertical baille, it), supported at the bottom by the boiler foundation. This baille wall, being vertical and of simple construction, and well supported, may be built of ordinary tire brick, laid with close joints, and so substantially impervious tothe furnace gases. This wall forces the furnace eases as they enter the heating ch-.nnlwr to tow, in the first instance, up ard along the bank of tubes 4,

and then downward along the tubes 5, thus insuring a relatively long path for the furnace gases in a relatively compact heating chamber comprising a relatively small number of banks of tubes. rl`he gases are nrther caused to cross tubes 4f at right angles when first enteringr the heating chamber, and to cross tubes 5 at right angles in passing from the heating.; chamber into thel otitalie l1. By means hereinafter described I further prolong the path of the furnace gases within said chamber and insure a very effet-tive action of the furnace gases on the tubes 4 and and on the under surface of the drinn l, which surface constitutes highly etlieient heating surface. Then the furnace gases tirst enter the heating chamber. a portion of said gases pass down, under and around the inud druui 3, and up through the spaces between tubes l, thus making drum 3 and tubes 6 etfeetirc as heating surface.

It. is well recognized that for etfectve transfer of heat. from furnace gases to heatingr surface. fresh portions of the gases should be iinpinging on the heating surface at all tintes. lf the gases inerely tiow parallel to 'the tubes of the boiler. there is a tendency of the' gases as do not inipinge upon tho tubes reaches the latter, it at all, only by transmission through the already-cooled bodiesv of gas. Furnace gases being extremely poor conductors .if heat, inereparallel i'low of the gases is productive of ine'lieiency, and is to oe avoided. To avoid thisdefect, it has been coininon to cause the gases to flow as nearly as possible transversely of the tubes, the entire currentl of furnace gases being caused to pur.' ze a very tortuous course, crossing and recrossing the same baul; of tubes a 'number of times. T he dcerts of this practice are, that considerable portions of the several tubes are prartioally outof the main current of furnace gases, and

are practically dead, that considerable por.

tions of the currents of furnace gases are at a considerable distance roin heating surface, and are tlieretore ine ective. that soinewhat compiti-ated ai'i'augciuentsof bathes are -required which for structural reasons are aptto be full of openings whichpermit short-circuitineT of the gases, and that the sides of the tubes opposite those on which the gas currents iuipinge are relativel)v ineffective as heating surface. To avoid the characteristic detect, above pointed out, of the incre parallel ilow of the gas( it is not necessary to go to the exti'enie of making the gases cross the tubes at right, angles, or nearly; so. It is sutlicient to cause the gases to ilow at a slight. angle to the tubes, thus producing. in etfec, a gradual translation Of Athe Current. of gases across 'the tubes while said current is flowing lengthwise of the tubes; by which translation fresh portions of the furnace are eoustautliv brought into .smart with the surface of the tubes, the gas is prevented from stagnatiug, so to speak, about said tubes. and all the henetts o se tlow of the tui-nace gases are. realized without considerable portions of said tubes being' oitl of the niain current( lily the arrangement f-f' transverse and longitudinal '-:ialll es, or their equivalents, ciuplojfed in my boiler, l prodn.,ze such a motion of translation of the currents of furnace gases with respect to the tubes while said g-.ises are flo :ng along the tubes. and at Athe saine' time cause thegases to flow in and ont around and between the tubes su that.

the heating of the tubes equalizefl, all portions of the surface oi' the tubes subgerted to suc.. nearly-parallel currents being subjected almost. equally' to tho action of such gases. so

that i'ifaetically the entire surface of each tube utilized in thtinost elleicut inanner as heatingsurfaee. Referring now to this feature of in v invention as embodied in the construction illustrated in the dra l provide the tivo banks et tubes, 4 and with four transverse baille walls 12. 13, 14 and 15,

longitudinal baille walls, 16 and 1T, (for the latter see Fig. 3) located between the transverse batllesl. and i3, and 14":m`cl'15, the i walls 1T on the inner side of euch bank of tubes, the walls 1G on the outer 'side of each shank. The longitudinal walls 16 and 17 are each relatively narrow, with spaces 18 between for the flow of the gases, there being a number of walls ltanfl, 1T for each bank of tubes, as shown particularly in Figs. 2 and 3. ln practice I customarily arrange groups, each group comprising a plurality tion shown), cach group separated from the adjacent groups by spaces somewhat wider than the distance between. the rows coinprising each group. Thus, iii the arrangenientv shown. the tubes of bank 4 are arranged in groups l, 4b, 4, etc., each conihanlr .3 are similarly arranged. The principal reason for employing this arrangement of tunes will be pointed out hereafter; but said arrangement has the important advantage. in this connection, of greatly facilitatins7 the use of ballles, or their equivalents, to

between the tubes, in a direction parallel to the front of the boiler, ineans to produce which forms one of 'the principal features of groups on the outer side' ot the banks 4t and 5, and similar-l)l ei'nploy walls 1T t0 close alternate spaces between groups on the inner side of banks 4 and 5, the intermediate spares between `groups, designated by numerals 1H, hein;i lefty open; but the alls 16 and 1i' are not opposite, but are staggered,

ell'ect is that gases entering' openings 1S between walls li oi" bank l, cannot pass (illiiecily through `mid openings to the ontsit e, but inns-t llow between the tubes, in :i dir'eetion parallel to the front of the boiler, to the spaces between the tubes of the adjacent groups. and tothe openings l beyond. This llow of the gases is' indicated by arrows in the drawings. By this arrangement of bafiles, the entire poi-tion of the tubes between tiansverse battles l2 and 13. and l-i and l5. are :surroiuided by furnace gases flowing not ,only longitudinally. but al o transversely. l with respect to said tut-es. in :i manner to insure the highest clliciency of heating surface. and to insurix substantially the saine elliriency for all portions oi' the heating surface of said tubes exposed to such currents. At the saine time. the gasesilow in a relatively direct path. and through openings of ample area. so that excessive draft is not l required. 'l` he tubes beingverif nearly verand I aiso provide said barksl of tubes with i tical, ash and (lust cannot collect on them,

of rows oie tubes itu-'o rows. in the construe cause the peculiar circulation of the gases.

my invention. The tubes being arranged in.' groups, as described, I einplj," the baille.'l walls 115 to close alternate spaces between the tubes ot' each bank in a plurality of prising two rows of tubes, and the'tubes of and so are the. openings ,l as a result. The

and therefore the transmission of heat is not interfered with bydeposits of such substances.

Instead of employing baille walls i6 and 17, above described, I may employ gener- Lland 5.

The primary reason why I prefer to arrange the tubes of banks Lt and 5 in groups, as shown, is to facilitate tubing and'retubingo' the boiler, and to permit the ready 2o removal of. any tube when desired. ln this connection I commonly employ drums 1, 2.

and 3 having tube-sheets of peculiar construction, so that to remove any tube, when ithas been freed at one end from the upper drum, for example, its end so freed may be moved slightly to one side, into one of the. spaces between groups of. tubes, vand then the tube may be lifted slightly, so as to unstep it at the bottom, after which itmay be 3o removed through one of the spaces 1S between groups of tubes. One construction of tube sheet which I may employ for this purpose is illustrated in Figs. S and 9. By pressing or otherwise. l `form a plurality of directly connected steps, 19a, 19", etc., the

aces of which steps are substantially perpendicular to the rows of tubes. llach such ste is usually of such width (longitudina ly of the drum) that it will take tubes of 4o all of the rows of the tube group to which it. corresponds, and it may be. of sutiicient length (transversely of the drum) to take more than one tube of each row. T his is true, in tbe construction shown, of steps 19a.

The tirst two or three' steps 'from cach row, (counting from the middle) as 19a. and 19", are commonly raised somewhat beyond the cylindrical surface of the drum, so that between them there are spaces or grooves 20 of such depth that when the end of a tube has been freed from its hole in such drum it may be moved over opposite such space or groove E20 (which spaces or grooves cor` respond tothe wide spaces 18 between the groups of tubes) and may then be moved longitudinally into such space or groove to permitfrceing of the other end of the tube from the drum to which it is connected. It is not necessary,` however, to raise completely from the surface vof the drum the steps which are well up or down on tbeside of the druin (as for example. steps 192, 19d, and 19C), as the tubes seated in such steps may be sprung outward, as well as to one side so as to permit them to be moved longitudinally enough Vto free their outer ends. Consequently the steps 19, 19d, and 19e are formed by pressing the metal partly in and partly out from' the true cylindrical curvature, as shown in Fig. 8, which shows sections on two planes, the left side showing a section through one series of steps, the right' side showing a section through one of the intervening spaces or grooves .20 between two series of steps. The steps of each series are directly connected, one to another, the extreme' opposite edges of each step being on o )posite sides of the mean curvature of the. rum, which mean curvature is maintained between said series. Furthermore, the general slope of-eachf series of steps conforms to the mean curvature .of the drum, and the use of man-holes is rendered un-V necessary. v

lie-sides of the raised steps 19 and 19b 35 form ribs which materially stillen the drum. In the construction shown, the faces. of the steps 19a of drum 1 are of a curvature ap proxiinating arcs of circles struck from the points of intersection of the mean axes of the tubes entering such surfaces, said surfaces being, therefore, approximately perpendicular to the tubes entering them. However I do not limit myself to giving such surfaces any precise curvature, or to giving them any curvature at, all.

The transverse baille-s 12, 13, 14 and 15 are composed of bars such as illustrated in Fig. 5, adapted to be inserted between the tubes edgewise, i. e., with their sides of greater width vertical, and then to be turned. hese battles are held in place by the pressure ofthe tubes against them, said tubesY being sprung apart, slightly, when inserting the battles, so that. when the tubes are released the battles will be held by spring action of the tubes. lreferably, the edges of the. transverse baillesv are grooved or corrugated, so as to surround partly the tubes adjacent to them.

Another feature of my invention resides in the construction of the baille Walls 16 and 17; and this feature 1s illustrated particularly in Figs. 6 and 7. Said walls are composed of sections 21 of tire-clay or other 115 suitable material, Asaid sections being each wider at one end than at the other, the narrow end of each sec-tion adapted to be insorted between the tubes, the wider end being too` wide for such insertion. The upper and lower faces of the sections are also inclined or beveled, the narrow end of each, section being higher than the Wide end. In setting,r up these sections, alternate sections (vertically) are inserted from opposite. sides o the tubes, the beveled surfaces matchin so that the wall thus formed is parallel wit the tubes, and tits closely thereto. The sections then key each other, so that they may not be displaced accidentally. T.t, will be noted that. the forni of the sections by which t this highlji1 cleiruble. keying together ia Secured. is u very 'simple one` and that. the ser" tions muy be niatle very easily.

Suitable doors 22 are provided to allori! acc-ess to the heating chamber at :i number of points. lt will be noted that. all parts of the boiler are ver): accessible. The hantl may he. placed on any tube or liatlle of the boiler, and in ease of breaking of the bullies. new ones may be puty in at anyv time. Tube.q may be taken out sind replaced without tlitliculty. The construction of the boiler is auch that there is :imple opportunity for expansion :intl contraction Without sti'ainin the part No stayed surfaces are required.

ln the operation of my boiler, the products; ot conihuStion from the coinliustion eliainher 7 tlirirle. part of them passing clii-oi-tiy across the bank of tulies 4, While another part of saiiil gaes pases down untlci drinn El, up across tubes 6. joiningl the first branch of the stream. Suid gases then p:

through the opvniugs i8 between battles l E of tubesl. between, around, :intl upn'zirtl along the said tubes. plis-sing out through Twingo 1S hetween baffles lt?. The garra ,ma pu-Q through the spaces betworn the Lutins, of earh group, which openings` are not elm-fil hy battles. either longitudinal or tranrerai. The peculiar circulation of the furnace gane? therein,7 prothiceil insuies the -unitorui heating' ot' the tuhes, in the inoet ellicient manner. new portions of the turnace gas@ heine' liroufzht constantly into contati with thi` tubes. The ,fasen then cross tiilii'." -l aint 5 trans.'cr;-'ol aliovo liatllosl 13 anrl ll, :intl lic-low th'iiui l` which ilruin is tlirrcln exposed to the limitinglr action of sairl gras-tis, iti' lower surfafe rou titutiu; rV effective heating .rt'zn-r. The ganen then pas? ueiii'er-n thix hallleu :it tubes .'i :intl circulate lictvfeft'u. arounil ainl alrng the saine in the saine manner .i.- with tuhrs l, hut passingr in thc oppozfite direction: :unl finally titl grasos 'pms acrossI tubes 5, lieloiv baille la, into the oil-take ll.

The gases' will hc materially cooler when they cnc-fuiutvr tiilnsq 5 thun when they en counlereil tnlusl. :intl therefore there will hv veriT rapiil circulation ot water l'from ilruin l ilowniraz-l through tubes 5 to '.iiuin thence tlirou jh tubes t3 to lruni 3, :.iitl l ence upward through tubes 4 to (li-nui 1. in. urin; r high capacity of the boiler in proportion to size unil heatingr Surface. The tubi-s 4 discharge directly, through iniolislrin'nwl opening. into (li-uni 1, :intl therefore the lisviigagonicnt of the steam from ilzv u'ater will taluplace almost entirely in ilruui l.\\hcre there is aniple i'ooni for Such elisvnguigeiiient. ln boilers in which the flow ot the water from the tubes to the lrnm is rest'iif-tcil, iliseugzligoment of Steam from the ii'ziter corietiniesnieeurs to n great extent in 1 i i l i l the tubes themselves; and this magy rrr-.ult in burning: oi the tubes. Sin-h burnin-f; is nnpossiblc in in v boiler, lion'ever. so hun! :is Si i proper water lei-el is niaiiirzini-il'. :intl irhile it. is desir-,thin that the, watt-r level #hall u i ways be aliove the bottoni of lrinn l. it ic known that such level may fall rouiil'irably below the liottoin of' the flrnni. the :ictiou within tuhcs 4 being sulliz-.ient to lfvep thi surfaces ot said tuhe anil the surface nt" the lower portion of the iiruni wat, eren ivhtrn the water level is brlov.' thebnttozn of druin l.

l. commonly introduce the. fer-.fl Water into drum l, `in proximity to the months of tubes 5, and Cause it to :nix with the water tiowing ilown through sfiid iuni into tli'uiu In thiS way the Water will he luatttl thoroughly to nienn lioilfi teinpczziturc. li\ lori: it eucount'erf the. tubes l, :iiii'l the f-'iilinient Whirh the feeil Water ina); roi-ry will hetltposih'rl in tlrui'n.c 2. :intl 3-the ino t ot it in tlruui Q uiii'ler normal Ponrlifion.

'lo insure tlry Strain, und keep the 'atri level the Sunni in all parts of the drinn l. l coinnioiil; take the steam oli' through a tlrv-pipe 23. perforated on top. ln prac, tice l have, found that if steam he taken oil at a fev pointn only` the n'atf-r lorf'l is niiifth higher below theI point.Q at which the steam i5 token oil than :it other points. 'l'hi rliypipe. extending Suliltantiallv fiorirou curl of the rlruni to the other, olii'iatw this.

To previ-nt projection of water from iulwH 4 upwaril into ihr: steam space ot' tliuiu l, may proriile. pcrtoratfi'l plate? il :ihoie the mouths of Said tuberi.

Brcausi. oi the t-llicieut. Circulation of aA lei' fn inv lioihi, aiirl the ver; ei'iir-ient. fiieuhitiondof the l'urinirr gage: .filling anil arountl the tuhfs anil other linut nl f Surfing". the liuilvr univ lip operatori. with high chr cieiitv, with rei-v strong iii-aft. anti thli= univ `lie t'oiciil tar lirjoi-:fl Whnt. :."cortliinlA to lortliuurv incthoih` ot rating, would lii consideri-(hitsy normal rzipacity. Thisl fact., :intl the :iliilitv ol 'the lfoilvr to og'wrzitc withv out iujurv eieii when the water loi'cl fullo far below. the noi'inal lei'cl. tfli'n-cially :nlapt :the lioiler for uw whore. the ocmcinil vario@ sutlileiili' through u'iile liiniia.

lt wll lio notctl that in)l 'finitrnctitin of ruhe short, ouahlrs nie to use strfiight, tulips. whit-li in the roiitruetion ot' boiler?y ol' this character is a matter of very lrent economic value.

I claim as niv invention l. ln v. hoilir, the combination witli n cirvnlatin;r n vraciii i-oiiipii;-iii :i plurality ot' flriiius, upper :intl lout-r, unil a plurality of connecting 'panics of grnei-:iz'inz iuhrs ai raugotl t'or circulation of natur lirziici-n mul upper unil lower tlruuna. of uic-:nw for illi'eiL-ting healing {aSes :iloig snifl nllios couiprisiincr srpnrate patcagp. varh nicloffnn! one of Quill banks of 1inir omini-ruhig tht' i. i Si erossing said tubes near the top ot' said wail and beioii said uppoi drinn. and other transierse ba iles erosng Said tubo.`V- at lower points.

13. )t boiler comprising :in upper and two lower druiuzs and banit` vof tubes; connai-ting said upper drinn i'o eaeli of Said lower li-na` in combination .vitii a beating eiiiimbr. in closing .Said tubes, and baring` a dividing baille will. transverse batlies in Said ebaiuber i'rossiug aid toben. and'longitudinal batiies ou oppoitisides of .i/ibanlis of tubes baviug staggered opening and nieaus for supplyiujr beating gases.

14. A boiler couipriaing au upper and two lower drums angl banks of tubos vouneeiing said upper drinn to eaeli of -@aid iowiirilrinns, in con'ibiiuitiini with a beating; f'iuunber iueloaing said tubes and baring 4a lliigidiiig baille wail, means for admittingbeating gases to ono side of said wail, transverse batiies on eiirli Side of said wail erosing Said tubes, near tbe top of Said wail and below ille upper ciriun, otiu'i-` trathsi'erse b.-itlie.\` crossing said tubes at loii'er points, and ion- IQiudinal bat' e.;between-tbetransversebatiies 2 baring staggered openings.

l5. Aboiier Comprising an upper and tivo lower drums and two banksl of tubes eai'iz eonneeting; haiti upper drain to one of ...aid

lower druin. in eon'ibinatiou with a beating initier ineliiduig Said tubos and hating a dividing baille wall between Said banks of E tubes and a source ot' supply of beating ou one side of said dividing u'ali and means l'or tbe esi'ape of Sueii gaan? ou tbe other side of Said wail. and transverse ballies for tbe first oi Said banks of tubos eauaiug tbe bez-.t-

vingr ,Qa. es to lion' ai'roSS and along tllev tubes.

lli. f\ boiler eoinprisingY an upper and two lower driuns and two banks of tubes. nach eounectiuer 'sind upper drum to one of said lower iii-luna. in combination with. a beating ebauiber nii-losing said tubes and baring a dividing baille wail between Said banks of tubeS and a Source of supply of beating gases ou one side of Said dividingwail and means for tbe escape of suifli gases on the other side ol said Wall. and transveize and longitudinal bullies i'ausiug said gaSeS to tlow across, along and around -aid tubes.

l'i'. boiler comprising an upper and two lower drains and two banks of tubes eaeii vonneeting said upper drinn tomne 0i said lower iiriuus. in eoiubination u'itb a lieatiug ebambi-r iuiloaiug; Suid tubes and having a dividing baille wall and a Source of supply of beating gases on one side of said dividing wail. and means for tbe. ewapo ot' suoli gases on tbv; other side of said wail. and transverse 'and longitudinal baiiii-s causing said gases to flow across, along and around said tubes.

1S. -X boiler comprising an upper and two louer drunib and two banks of tubes eaeli connecting said upper drinn to one. of said other near tbv other tuti E said longitudinal l lower drinne. in eon'ibination with a lit-ating: ebuniber inelosiugf said tiilr-e and baring a dividing baliio wail and a Source of Rupp j: of beating gases ou one sida of :said divitline1 wail. and moans for iiie efeape of siiib gaies on tbe oiiierviiie of said Wall. and lvm trans verse bullionV for ifai-ii baul; nl' tiilw, ne located near tiw ioii'ei end tiiereot and 'tbe i thurs-ot.

19. i boiler compr uppf-r and two lower drunia :mii tivo banic of tub'ts web connectingf Said upper drinn to one of :raid lower driuus. in eoiiibinatioi'i with a beating iiianiL-rduelo/sing Said tuiw" and having; :i dividing ii'zitiie, wail and :i uren ot' :.iippiy of beatiin;r gamas on one f'. of aid rbviding ou i'lw` .other a .le ot' e. idV wail. transi'ir bolliniv tor one or bolli of said bai-.lis of tubos located one i.i-:uf the lower and thereof :ind another :wai the upper vii-'i thereof, and longitudinal baliie: between .Caid trunSverSo bullies.

"0. ln :i boiler. tbe eombinzition with o. s of genio-ating tuig-es. and a lairalint` ebfiinbe iii-living tia- Sanie baring ioosim for .Qnpp :ing beating asve'anil an nti-taire. of longitudinal batiii' lo said series of tubef. ioiated on opposite sides of said Serie?, .staggered openings i,et\\'eru ,Laid battles bebij.;i provided for tbe tion: of beating games armas the. tnb.

2l. ln a boiler. tbe riniziauation with a Siries of generatinw tubos. and a beating rlizunber hielos-ing ibix saine baring moans for supplying iii-ating"r i and :in olitalu. of longitudinal and transverse battles for said series ot' tiibet. il; "uigiinilinai buf lies loi'aiod on opp i staggered openings biaii'cen f nal baiiit-s beingT provided for tbe. liiuw of the .ting gases. aio-ng and. aeros, :iid tubes.

A boiler romp isiug two drums, se ies ien voniaeeting tiie saine, and a beating er inf-losing said aries of tubes and ot tu.

.liu .ig means for supplying heating.r gae's of tubeS ci'innecting;r tbe Sani?, and a Abeating eli-amber inelosiug; sani Series of tubesanci having means for :aippiyinui heating gases and an oli-take,l in combination with-longitudinal and transverse baliles for said series of tubes` tiie former located on opposite sides of the .Qi-ries. Staggorefi openings between ile-s being provided for tbe limi' of beating;f gases along and across said tube-s.

24. A boilei compr ng an up Jer and two lower drums, and two banks o tubes each connecting said upper drum to ou' of said longitudinal batlles being provided for the tlow of heating gases along and across said tubes.

25. A boiler comp ising an upper and two lower drums, and two banks of tubes each connecting said upperdrum to one of said lower drums, in combination with a heating chamber inclosing said banks of tubes, having a dividing baille wall between said banks of tubes and an oil-take on one side thereof, a furnace outside of said chamber connected thereto on the other side of said wall, and upper and lower transverse battles and longitudinal baliies for each bank of tubes, staggered openings between said longitudinal batiies being provided for the iow of heating gases along and across said tubes.

:26. A boiler comprising an upper and two lower drums, and two banks of tubes each Y connecting said upper drum to one of said lower drums, in combination with a heating chamber inclosing said banks of tubes and having adividing battle wall between said banks of tubes, 'upper-and lower transverse battles and longitudinal battles for each bank of tubes, staggered openings between said longitudinal batlles being provided, said heating chamber having on one side of said dividing wall an inlet for heating gases located below the lower transverse baiile on that side, and having on the other side of said wall an off-take located below the lower transverse baille on that side, said chamber having also a passage above said upper transverse battles connecting the two sides of said chamber.

27. ln a boiler, a. tube sheet of curved configuration, having series of continuous steps,` and unsteppcd plain surfaces interveningr between each of said series, a scction taken through said series of steps in tersecting at the treads and risers thereof a )rejected section of the curved sheet taken between any two of said series of steps.

Q8. A boiler-drum having its tube-engaging sheet curved in conformity to the re.- mainder ot the drum, and having in its surface a plurality of series of steps, for the `reception of the boiler-tubes, all the steps of each series being directlyv connected, one to another, the extreme opposite edges of each step being on opposite sides of the mean curvature of the drum, which mean curvature is maintained between seid series to form transverse spacesv for facilitating the insertion and withdrawal o'f the tubes.

29. A boiler-drum having its tube-engaging sheet curved and formed in its surface with a plurality of series of steps, for the reception of the boiler-tubes, said series of steps being` separated by transverse spaces which facilitate the insertion and withdrawal of the tubes, the general slope of cach series of steps conforming to the curvature ot the tube sheet at said transverse spaces, and the extreme opposite edges of each step beingon opposite sides of auch curvature.

30. A boiler-drum having its tube-engaging sheet curved in conformity to the remaining portion ot the drum, and having in its surface a plurality of series of steps, for the reception of the boiler-tubes, the general slope of each series of steps conforming to the cylindrical portions of the drum intervening between said series of steps, said facilitating the inserintervcning portions tion and withdrawal ot' the tubes.

231. ln a water tube boiler, a plain drum having separate tube landings formed therein, in parallel rows, and so arranged as to leave suliicient space between the adjacent transverse rows for the insertion or withdrawal of the tubes from either .side of a row without the use of manholes, as described. l

32. ln a water tube boiler, a plain drum having parallel rows of Separate circular tube landings formed partially above and partially below the drum Ylace, and so aranged as to leave suliieient space between the adjacent transverse rows for the insertion or withdrawal of the tubes from either side of a row without the use of manholes, as described.

33. In a boiler, the combination with a series of tubes arranged in groups, each comprising a plurality1 of rows, the spaces between groups being wider than the spaces between adjacent` tubes ot a group, of longitudinal battles located on opposite-sides of said series of tubes and obstructing alternate spaces between groups, but leaving open the intermediate spaces between groups, such open spaces on opposite sides ot' the series being staggered.

34. lu a boiler, the combination with a series ot' tubes arrangedr in groups, each comprising a pluralityof rows, the spaces between groups beingwider than the spaces between adjacent tubes of a group, of longif tudinal and transverse batiies for said tubes, the longitudinal battles being located between tlie transverse battles and on opposite sides of said series oftubes, and obstructing alternate spaces between groups, but leaving open the intermediate spaces between groups, such open spaces on opposite sides of tie .ries of tubes being staggered, and a. heating chamber inclosing said tubes and provdurl with means dxvong lwntnggrzysvs l und groofd o1- uorrugzxled on sides adjaiou'url tbv opcnugs between long'ludnul i von( to Sad tubos, said bnvs ftug tightly 20 bumwy on one sido of tlm serios of tubos. ngnnsl ibn adjacentubes und held in place 35. 1u :x bolor, tbc coxnbnaton with :x by spring :1f-Hon of huid tubos.

5 s'vl'vs o tubes arranged. in groups mob In n bolm, the combination with a voxulnsng a pbnaliy ot' rows, the spaces pbuniiy of tubos, of d humo-wall comprisbvwmu groups being wider iban tbv spzxco I between ndjucent tubo; of n group, of tlnnsibo mlm'. ibo nnlxowvr ends of sfxd Secworse bnilles l -ntvd in such spaces. beiwovn f lim longur than tbc wider ends thereof,

10 groups, tho Spncos buiwocn rows bvng open. .Quid smlion :ux'nngod in series with their 3G. In a boiler, tbc omubnuon with pnrwirkx :nul nnrrow faros :xlivrnnivly on oppo- :xllcl inbcs7 of om m* moro bnlos urrunggod sito ub-.Lz mi' mid lube?. 3o between and transvcrclv of said tubos, and 1n iolbnoxq whoa-mf I bvrounio nx my hold in place by sning-nciion of mid tubos sgnniurv. u thv prvssnvo of (wr. w'unesses. 

